On 30/12/2025 1:54 pm, Andrew Cooper wrote:
> diff --git a/xen/arch/x86/xstate.c b/xen/arch/x86/xstate.c
> index 384f78bd5281..4215a83efefb 100644
> --- a/xen/arch/x86/xstate.c
> +++ b/xen/arch/x86/xstate.c
> @@ -310,21 +310,21 @@ void xsave(struct vcpu *v, uint64_t mask)
> uint32_t hmask = mask >> 32;
> uint32_t lmask = mask;
> unsigned int fip_width = v->domain->arch.x87_fip_width;
> -#define XSAVE(pfx) \
> - if ( v->arch.xcr0_accum & XSTATE_XSAVES_ONLY ) \
> - asm volatile ( ".byte " pfx "0x0f,0xc7,0x2f\n" /* xsaves */ \
> - : "=m" (*ptr) \
> - : "a" (lmask), "d" (hmask), "D" (ptr) ); \
> - else \
> - alternative_io(".byte " pfx "0x0f,0xae,0x27\n", /* xsave */ \
> - ".byte " pfx "0x0f,0xae,0x37\n", /* xsaveopt */ \
> - X86_FEATURE_XSAVEOPT, \
> - "=m" (*ptr), \
> - "a" (lmask), "d" (hmask), "D" (ptr))
> +
> +#define XSAVE(pfx) \
> + if ( v->arch.xcr0_accum & XSTATE_XSAVES_ONLY ) \
> + asm volatile ( "xsaves %0" \
> + : "=m" (*ptr) \
> + : "a" (lmask), "d" (hmask) ); \
> + else \
> + alternative_io("xsave %0", \
> + "xsaveopt %0", X86_FEATURE_XSAVEOPT, \
> + "=m" (*ptr), \
> + "a" (lmask), "d" (hmask))
This loses the pfx. I've fixed up locally and double checked the
disassembly.
~Andrew
